Cell phone use and two-way communication systems in automobiles are facing scrutiny again, this time from the Center for Auto Safety (CAS).

In a letter directed to the National Highway Traffic Safety Administration (NHTSA), CAS Executive Director Clarence Ditlow petitioned for new laws to restrict the availability of two-way communication, including cell phones and services like General Motor's OnStar and Volvo's On Call. According to the letter, automakers have begun enhancing services like OnStar by offering additional features that allow drivers to gain access to e-mail, movie listings, and customized news reports, a trend CAS views as dangerous because it adds to the already long list of driver distractions. Ditlow said that the potential distractions are similar to permitting television monitors in the front seats of passenger vehicles, a practice that is not permitted by most state laws. He also said that the accident experience of drivers using cell phones has been shown to be similar to that of drunk drivers, noting statistics that show both behaviors increase the risk of a vehicle crash by four times.

The CAS proposed language for the law, which says, “Any vehicle integrated personal communication systems including cellular phones and text messaging systems shall be inoperative when the transmission shift lever is in a forward or reverse drive position.” In addition, CAS petitioned NHTSA to consider subjecting other vehicle integrated telematic systems such as OnStar into the proposed amendment.

“Research consistently has shown that operating a motor vehicle while talking on a cell phone — whether hand-held or hands-free — increases the risk of an accident to three to four times the experience of attentive drivers,” said Ditlow, in the letter to NHTSA. “The two-way conversation on a cellular phone, not the task of holding the phone, causes a cognitive distraction. This distraction induces inattention blindness, which inhibits drivers' abilities to detect change in road conditions.”